Vapor-liquid equilibrium for dimethyl ether and 2-methylpropane

The vapor-liquid equilibrium (P, T, x, y) for dimethyl ether and 2-methylpropane was measured at 280, 290, 300, 310, and 320 K by the dynamic method with recirculation of the vapor through the liquid phase. The composition was measured by a gas chromatograph connected "on-line" to the equilibrium cell. The response of a flame ionization detector was calibrated over a wide composition range using mixtures being prepared by mass. The experimental results were reduced by the Carnahan-Starling-De Santis equation of state assuming that its binary interaction parameter was temperature independent. The system is azeotropic with strong positive deviation from Raoult's law.